Thermal detector



FIG. 1 is a plane view of a thermal detector in accordance with the design;

FIG. 2 is a front view of the thermal detector of FIG. 1;

FIG. 3 is a bottom plane view of the thermal detector of FIG. 1;

FIG. 4 is a left side view of the thermal detector of FIG. 1;

FIG. 5 is a right side view of the thermal detector of FIG. 1; and,

FIG. 6 is a back view of the thermal detector of FIG. 1. 

The ornamental design for a thermal detector, as shown and described. 